﻿CONTENTS. 
  

  

  PART 
  I. 
  

  

  I. 
  On 
  the 
  Volcanic 
  Geology 
  of 
  the 
  Vivarais 
  (Ardeche). 
  By 
  James 
  D. 
  

   Forbes, 
  Esq., 
  F.R.S., 
  Sec. 
  U.S. 
  Ed., 
  Professor 
  of 
  Natural 
  Philoso- 
  

   phy 
  in 
  the 
  University 
  of 
  Edinburgh. 
  (With 
  Six 
  Plates.) 
  . 
  1 
  

  

  II. 
  On 
  a 
  Process 
  in 
  the 
  Differential 
  Calculus, 
  and 
  its 
  application 
  to 
  the 
  So- 
  

   lution 
  of 
  certain 
  Differential 
  Equations. 
  By 
  the 
  Rev. 
  P. 
  Kelland, 
  

   M.A., 
  F.R.SS.L. 
  & 
  E., 
  F.C.P.S., 
  late 
  Fellow 
  of 
  Queen's 
  College, 
  

   Cambridge 
  ; 
  Professor 
  of 
  Mathematics, 
  &c, 
  in 
  the 
  University 
  of 
  

   Edinburgh, 
  ....... 
  39 
  

  

  III. 
  On 
  the 
  Constitution 
  of 
  Codeine 
  and 
  its 
  Products 
  of 
  Decomposition. 
  By 
  

  

  Thomas 
  Anderson, 
  M.D., 
  . 
  . 
  . 
  . 
  .57 
  

  

  IV. 
  On 
  the 
  Equilibrium 
  of 
  Elastic 
  Fluids. 
  By 
  Mr 
  James 
  Clerk 
  Maxwell, 
  87 
  

  

  V. 
  Dissertation 
  on 
  a 
  Peruvian 
  Musical 
  Instrument 
  like 
  the 
  Syrinx 
  of 
  the 
  

   Ancients. 
  By 
  Thomas 
  Stewart 
  Traill, 
  M.D., 
  F.R.S.E., 
  Profes- 
  

   sor 
  of 
  Medical 
  Jurisprudence 
  in 
  the 
  University 
  of 
  Edinburgh. 
  (With 
  

   a 
  Plate.) 
  ........ 
  121 
  

  

  VI. 
  Some 
  Remarks 
  on 
  the 
  Theories 
  of 
  Cometary 
  Physics. 
  By 
  C. 
  Piazzi 
  

   Smyth, 
  Esq., 
  F.R.S.E., 
  F.R.A.S., 
  Professor 
  of 
  Practical 
  Astrono- 
  

   my 
  in 
  the 
  University 
  of 
  Edinburgh, 
  and 
  Astronomer-Royal 
  for 
  

   Scotland, 
  ........ 
  131 
  

  

  VII. 
  On 
  the 
  Mechanical 
  Action 
  of 
  Heat, 
  especially 
  in 
  Gases 
  avid 
  Vapours. 
  

   By 
  Wm. 
  J. 
  M. 
  Rankine, 
  Civil 
  Engineer, 
  F.R.S.E., 
  F.R.S.S.A., 
  

   &c, 
  ........ 
  147 
  

  

  VOL. 
  XX. 
  b 
  

  

  